For Ethernet aggregation/backhaul of Layer 3 services, conflicting customer MAC addresses may occur (e.g., for customer edge routers or customer premises equipment, or “CEs/CPEs”), especially given the diverse set of Ethernet equipment manufacturers that may not adhere to the standard that each device have a unique MAC address. For example, for a service provider with millions of DSL (digital subscriber line) ports, there can be a number (e.g., hundreds) of duplicate MAC address alarms active on the DSLAMs (DSL access multiplexers) at any point of time where two of the same MAC addresses appear on the same DSLAM. When such overlapping addresses occur, the CEs/CPEs often experience traffic black-holing without any corresponding feedback from the network.